• SJSU Singular Matrix Database
  • Matrix group: HB
  • Click here for a description of the HB group.
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  • Matrix: HB/can_61
  • Description: SYMMETRIC PATTERN FROM CANNES,LUCIEN MARRO,JUNE 1981.
  • download as a MATLAB mat-file, file size: 2 KB. Use SJget(79) or SJget('HB/can_61') in MATLAB.
  • download in Matrix Market format, file size: 1 KB.
  • download in Rutherford/Boeing format, file size: 977 bytes.

    HB/can_61

    Routine svd from Matlab 7.6.0.324 (R2008a) used to calculate the singular values.

    HB/can_61

    Matrix properties (click for a legend)  
    number of rows61
    number of columns61
    structural full rank?yes
    structural rank61
    numerical rank 49
    dimension of the numerical null space12
    numerical rank / min(size(A))0.80328
    Euclidean norm of A 10.947
    calculated singular value # 490.070452
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    1.0836e-013
    calculated singular value # 501.2144e-015
    gap in the singular values at the numerical rank:
    singular value # 49 / singular value # 50
    5.8012e+013
    calculated condition number1.4014e+036
    condestInf
    nonzeros557
    # of blocks from dmperm1
    # strongly connected comp.1
    entries not in dmperm blocks0
    explicit zero entries0
    nonzero pattern symmetrysymmetric
    numeric value symmetrysymmetric
    typebinary
    structuresymmetric
    Cholesky candidate?yes
    positive definite?no

    authorL. Marro
    editorI. Duff, R. Grimes, J. Lewis
    date1981
    kindstructural problem
    2D/3D problem?yes
    SJid79
    UFid102

    Ordering statistics:AMD METIS
    nnz(chol(P*(A+A'+s*I)*P'))361 397
    Cholesky flop count2.2e+003 2.8e+003
    nnz(L+U), no partial pivoting661 733
    nnz(V) for QR, upper bound nnz(L) for LU434 529
    nnz(R) for QR, upper bound nnz(U) for LU1,017 1,122

    Maintained by Leslie Foster, last updated 24-Apr-2009.

    Entries 5 through 14 in the table of matrix properties and the singular
    value plot were created using SJsingular code. The other plots
    and statistics are produced using utilities from the SuiteSparse package.
    Matrix color plot pictures by cspy, a MATLAB function in the CSparse package.